WordPress at a glance
function is not described

_get_template_edit_filename() WP 2.9.0

Tidies a filename for url display by the theme editor.

No Hooks.

Return

String.

Usage

_get_template_edit_filename( $fullpath, $containingfolder );
$fullpath(string) (required)
Full path to the theme file
$containingfolder(string) (required)
Path of the theme parent folder

Code of get template edit filename: wp-admin/includes/theme.php WP 5.2.1

<?php
function _get_template_edit_filename( $fullpath, $containingfolder ) {
	return str_replace( dirname( dirname( $containingfolder ) ), '', $fullpath );
}